SW1X Audio Design™ AMP IV “Aura” Performance Level 3/4/5 2A3 DHT Integrated Amplifier   AMP IV is a Pure Class A Amplifier coupled with a High Quality Pre-amplifier using our in house designed and in house made stepped attenuator volume control. The Directly Heated 2A3 Triodes at the output are well known for their linear … Continue reading SW1X AMP IV “Aura” Integrated Amplifier